Method of treating balatas and gutta-perchas



I .1, 1, Jan. 18,1927. I I C'HSMITH 6 4541 METHOD OF TREATING BALATAS AND GUTTA PERCHAS INVENTOR Claude H. Smith K AT RN EY Patented Jan. 18, 1927. y I p a u mrso STATES PATENT OFFICE.

. CLAUDE SMITH, OF AKRON, OHIO, ASSIGNOB TO THE GOODYEAR TIRE 8 RUBBER COMPANY, OF AKRON, OHIO, A CORPORATION O! OHIO.

Applieation filed December 13. 1924. Serial No. 755 811.

My invention relates to the manufacture A decolorizing agent is added to this soluof balata and gutta-percha' products and tion, while being agitated andthe suspenit. has, for its primary object,the provision sion, thus formed, is allowed to settle. of a method of purifying,'decolorizing and have provided a special settlingtank 5 for 6 concentrating the crude material. this ste which .is connected to the dissolv- Another object of my invention is to proing tan 1 by the conduit, 6. Tap pipes '7 vide a method of treating low qualitybalatas connected at diflerent levels to the settling or guttaerchas ,to obtain productshavtank 5 are used to draw oil supernatant liqing a uni ormly excellent quality.- uid, which results from. the settling procis available on the market is colored, resinous tank 8, prior to its filtration. The tank and has con iderable foreign matter incoris provided with an agitating device 9 which poiated therein. Moreover, even when parserves to suspend a filter-aid employed to ticular care is exercised in collecting and facilitate the filtration. The suspension is coagulating its latex, it is of variable comconducted to a pump 10 which forces it un- 7 osition and color. Many processes have dcr pressure through a filter press 11. The been devised to" make this material more filtrate is then conducted through a suituniform and desirable for its respective uses. able conduit 12 to a storage tank 14. In some cases, the material is milled in the When gasolene is used as the gum solvent.

F 1 presenceof a water spray and the foreign the decolorized product may readily be re- 7 matter is thereby removed. In other proccovered by merely chilling the clearbleached esses, a bleaching powder is incorporated hltratea This is readily accomplished by during the milling process. While in still means of any suitable cooling device whether other methods, ulfur dioxide or chlorine continuous or intermittent in character. I is used to efiect a decolorization. These have found a freezer mechanism, such as inmethods of purification and decolorization dicated at 15, conveniently applicable. The react destructively on the balata and, in filtrate is fed from the storage tank 14 many instances, the color reappears. Furthrough a pipe or hose connection 16 to the thermore, if. the resinous material, which freezer device. The chilled suspended prodmerely acts as a diluent for the pure gum, uct is poured into a funnel arrangement is not completely removed it will impart a 17 and conducted to a' storage tank 18 through a conduit 19- The storage tank 18 color to the product.

In this invention, I have provided a' is provided with a stlrring device 20 in ormethod of removing the color, resins, an der to maintain the suspension.

" foreign matter from crude balata or gutta- The two phases of the mixture may be a decolorizing agent and recovering the dethe solvent through suit perch-a, and 'thereby obviate .undesira e separated'by any convenient means. I have qualities. Briefly, the process involves exrovided a centrifuge arrangement 21 which tracting the resins with 'a suitable solvent, is fed from the suspension storage through .mixing a solution of resin-free material'with a pipe 22. A pump 23 is provlded to force.

a le pipe conneccolorized solute. tions to a storage container 25. Finally The accompanying drawing is a diathe solid phase product is dried, preferably rammatic view illustrating the operations in a vacuum drier not shown. involved in practicing my invention. A large number of solvents are suitable 45 The crude balata; reterably in chi ped for extracting the resins, among which are form,'-is placed in a tank 1 where it is s owacetone, chloroform, any volatile hydro-carly agitated in the presence of a resin solbon, et al. .I prefer to use a high test gaso vent by some suitable-device, such fpr exlene, because the same solvent employed to ample as indicated at 2. The tating extract the man may be used in dissolving device is driven by mew: a pu ley arthe resin-free balata, by merely controlling rangement 3 from some sou of power, not its temperature.

shown. The de-resined material is then dis- While it is true, that the resins may be solved in a pure solvent, with the aid ofheat extracted morerapidly and more completely lied from a seam jacket 4, which par- 'with hot acetone, this involves the use of at S11 t i ll l the tank 11 le t t o mor -e p e lv nts Gaso- The crude balata and gutta-percha that ess. These conduct the liquid to a storage 65 len e'has an added advantagle, in that the In the. descrip ion and claimsthe word 7 gum is practically insoluble t ereinat a'low gum? has been used to designate the rub-- temperature. This-obviates the necessity-of her-like product which results after the I adding a p'recipit ting agent vto the sol-vent, resins have been extracted from the crude? .which'in turn must 'be separated before itis balata o'r gutta-percha. I again available for use in the process. A Although I have outlined but one method counter-current extraction of'the r'esins is v of ap l ing the principles of my invention,

- advantageously. applicable, after which the it is o vious to anyone skilled in the art that solvent may, ofcou-rse, be freed of'i-ts resin 'many apparently widely difl'erent proceby any suitable means, such as distillation dures may he followed without de arting $5 or preci itatio'n. a a V c from the spirit of the inventionan j.I (le- Any ecolorizing agent may be utilized. sire, therefore, that it shall be limited only v I havefound fullers earth veixiy satisfactory in accordance with the appended claims.

because it is white and ters readily, What I claim is: u

whereas bone char leaves small .artlcles of. 1. A process .of purifying resin contain- 0 black material in solution, whic ma not ing balata or gutta-percha that comprises be readily removed Furthermore, ue to attracting theresins witha solvent progres- ';its'chenti cal inertness, fullersearth has a sive'ly lower in resin content, dissolving the decided advantage over... bleaching :powdr,.flde-resined material in fresh solvent,"-"inti V sulfur-dioxide or chlorine and itmay be mately mixing the resultant solution with revivifiedand' utilized any number ofjtimes an inert. decolorizing 'agent, removing the by merely washing it with a suitable solvent "agent and finally precipitating" the-balata' or byheating in the'presence of ain f product. a uantity'of fullers eartline'oessary tor sans-.1 2. A process of. purifying resin contain? atory results varies with th e quality of ingibalata or gutta-percha thatQbompi'ises-" the raw material, generally"one of e tractingthe resins with a solveht'piogres practicingmyunvention. However, I prefer matelyl- 'fullers earth therewith,"

decolorizr is'sufliclent to treat three pounds 's1 vely lower in resin content,.diss olving the of crude stock. L de-resined material in a freshysolvenh de The. process is not-necessary 1n colorizing the resultant solution' by intito add this step bebause it reduces-the necesfiltering the suspension, chilling the .de-

y the lad sa y capa i y of t e 1 :pre8S. LikeWiS, eoIorized-solution thereby precipitating-the 'tion 'o f,a filter-aid to p the superproduct, and drying the product, v

natant liquid is o tional ,at the discretion f-igA process ofpurifying balataor gutteof the operator; e added-Ste isvadyis percha that comprises extractingthe'resin's,'- able, because the filter-aid adson the .in-, intimatelymixing powdered fulie'rls earth.- soluhle material which would. otherwise with a vsolution of the resin-free bala'ta, re- 7 'form a'. thin im rvious coat 1ontheT-.-filter; movingithe suspended matter, chillin the V cloths, and there y retard thefiltration. solution, to precipitate the-balat centrifug-l' It is also to be 1. derstood,'-.thati mgt'he precipitated product anddrying' it yention'is' notdimited to 'anysh gle-rmeani i in apartifal'fva'cuum. a v of agitation, and, although I: Zhave suggested In, witness whereof, I, hayefliereunl'o -ithe use of mechanical stirreiis, othe1 Ps gned my name, means ma beused,inprg'vxtleing myinvem j tion, as, orex ample, ain-.1, s

j muss liq-shi t ng 

